Journal of Materials Chemistry A
·
2019
·Vol. 8
·期 2
·789-796
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IF 10.733
Yangyang Zhan,Zhibin Shao,Tianhao Jiang,Jing Ye,Xiaofeng Wu,Bingchang Zhang,Ke Ding,Di Wu,Jiansheng Jie
Two-dimensional (2D) vertical heterojunctions possess peculiar electronic and optoelectronic properties according to their complementary composition, ultrathin thickness, and unique geometry. However, it is still a challenge to synthesize 2D vertical heterojunctions based on non-layered materials due to strong covalent bonds and abundant surface dangling bonds. Here we developed a partial cation exchange method for the synthesis of 2D vertical Cu2S/CdS heterojunctions. Large-size and single-crystalline CdS nanosheets prepared by a van der Waals epitaxy method served as host lattices for cation exchange reactions. The evolution of the nanosheets in terms of their morphology, composition and crystal structure was elaborately characterized. The as-prepared 2D vertical heterojunctions have two-layer ultra-thin structures and form large-area junctions at their interfaces. Under light irradiation, the photogenerated electron–hole pairs can be quickly separated under the electric field in the junction region, minimizing the possibility of charge recombination. As a result, the device based on 2D vertical Cu2S/CdS heterojunctions exhibits a higher photoelectric conversion capability compared with the device based on single-component 2D CdS or Cu2S Schottky junctions. Our work opens up opportunities to explore 2D vertical heterojunctions based on non-layered materials for high-performance optoelectronic devices.
研究领域:
材料科学
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纳米科技
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半导体物理
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光电子学
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能源材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 46
·23773-23779
·
IF 9.931
Zhiyuan Wang,Ruqin Zhang,Min Zhao,Zhongqiang Wang,Bingwei Wei,Xuefeng Zhang,Shuai Feng,Hailiang Cao,Peizhi Liu,Yuying Hao,Hua Wang,Bingshe Xu,Stephen J. Pennycook,Junjie Guo
High-performance organic photovoltaics (OPVs) are of great scientific and technological importance due to their potential large-scale industrial applications. Introducing semiconductor quantum dots has been proven to be an effective way to improve the power conversion efficiency (PCE) of OPVs. In this paper, we report a novel approach to fabricate atomically thin antimonene quantum sheets (AMQSs) possessing a uniform size (≈2.2 nm) via imidazolium ionic liquid-assisted exfoliation. In this method, the yield of AMQSs (1.1 mg mL−1) has been increased by nearly two orders of magnitude compared with that of previously reported methods. Furthermore, upon adding AMQSs into the light absorber in OPVs, the optimal device with 1.0 mg mL−1 AMQSs shows the highest PCE of 9.75%, resulting in over 25% enhancement in PCE compared to that of the reference device. It also leads to a noticeable enhancement in the short-circuit current density (Jsc) of 16.7% and the fill factor (FF) of 8.4%. The increased PCE is mainly due to the two-dimensional electronic structure of AMQSs that can enhance the light absorption, assist exciton dissociation and reduce charge recombination of OPVs. This work provides a new avenue toward mass production of two-dimensional quantum sheets and points to a new strategy for highly efficient OPVs.
研究领域:
材料科学
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纳米科技
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光伏技术
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半导体物理
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能源材料
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Hui Chen,Jinfeng Wang,Chenchen Jia,Junpeng Mou,Lei Zhu
For the purpose of increasing the power conversion efficiency (PCE) meanwhile decreasing the cost of dye-sensitized solar cell (DSSC), Cu 2 ZnSnS 4 - multiwall carbon nanotubes (CZTS-MWCNTs) nanohybrid Pt-free counter electrode (CE) was prepared via a facile fabricating route. In brief, CZTS nanoparticles were synthesized by a solvothermal method and the composite film was fabricated by spin coating the aqueous solution of the composite. The short-circuit current density and PCE of the DSSC with CZTS-MWCNTs CE were found to be 16.62 mA cm −2 and 9.04%, respectively. But the corresponding values were 15.42 mA cm −2 and 8.74% for a DSSC with a pure Pt-CE. This is owing to the synergistic effect of the intrinsic superior electrocatalytic activity of the CZTS nanoparticles and highly specific surface area and high electrical conductivity of the MWCNTs . The presence and distribution of CZTS-MWCNTs on the CE were characterized by X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM), respectively. Cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were examined for confirming the high electrocatalytic efficiency of this nanohybrid system.
研究领域:
材料科学
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能源化学
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纳米技术
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电化学
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光伏器件
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·Vol. 12
·期 5
·4610-4618
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IF 1.5
Chenle Zhang,Libo Deng,Peixin Zhang,Xiangzhong Ren,Yongliang Li,Tingshu He
Electrocatalytic NiS 2 cubes were directly synthesized on F-doped tin oxide using a hydrothermal approach and used as counter electrode in dye-sensitized solar cells (DSSCs). The NiS 2 cubes displayed an excellent electrocatalytic activity in the reduction of I 3 − showing a power conversion efficiency of 5.56%, which is close to that of the Pt-containing DSSC (7.05%). Furthermore, the NiS 2 cubes showed a comparable stability to Pt. This is ascribed to the low resistance to diffusion and transfer of electrolyte ions. These results suggest that the NiS 2 cubes prepared through a facile process is a promising substitute to Pt electrode.
研究领域:
材料科学
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能源化学
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纳米材料
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电化学
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光伏器件
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·Vol. 43
·期 8
·6257-6262
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IF 2.986
Zhongdong Zhao,Yihan Qi,Qiuying Chen,Xuerong Zheng,Qiuyan Hao,Wen Zhang,Jing Mao,Caichi Liu,Hui Liu
Compared with the expensive and complicated vacuum techniques, the solution-based process to deposit I-III-VI 2 chalcogenide thin films (I=Cu, III=In or Ga, VI=S or Se) has attracted great interests due to its lower cost, higher scalable production and better application in flexible substrate . Herein, a low-toxic and high-active mixture solvent comprised of 1, 2-ethanedithiol and 1,2-ethylenediamine is utilized to dissolve elemental Cu, In and S powders at 60 °C, forming the CuInS 2 (CIS) precursor solution . After spin coating and annealing in a both Ar gas and selenium atmosphere, a dense and large-grained chalcopyrite CuIn(S,Se) 2 (CISSe) thin films with a close-packed grain size of ~800 nm are prepared, eliminating a undesired fine fine-grained bottom layer. In addition, the selenization temperature of the CISSe thin films is also discussed, which influences the phase composition, crystallinity and morphology of CISSe thin films. Photovoltaic device of the CISSe-based thin films is fabricated, obtaining a power conversion efficiency of 6.2% with an active cell area of 0.5 cm 2 under AM 1.5 illumination.
研究领域:
材料科学
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薄膜制备
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光伏器件
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无机功能材料
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半导体材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 5
·期 8
·5604-5610
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IF 3.708
Mei Yu,Jindan Zhang,Songmei Li,Yanbing Meng,Jianhua Liu
The performances of photovoltaic devices can be improved by increasing light-harvesting and charge collection respectively. The design and synthesis of nanocomposites with the ability of enhancing the generation and collection of the photo-generated electrons provide a significant way to improve the power conversion efficiency (PCE). Herein, SWNTs@(TiO2/Ag/Au) nanocomposites were synthesized and successfully integrated into photoanode films of dye-sensitized solar cells (DSSCs) to improve the power conversion efficiency. The synthesis processes were based on multi-functional DNA. DNA not only works as a dispersing agent preventing SWNTs bundling but also as a sacrificial mold assembling TiO2, Ag and Au nanoparticles on the surface of the SWNTs. The synthesized SWNTs@(TiO2/Ag/Au) nanocomposites enhance the charge collection and light-harvesting of DSSCs simultaneously. With 2.45 wt% SWNTs@(TiO2/Ag/Au) nanocomposites incorporating into the photoanode films, the PCE of the DSSCs increases from 6.8% to 8.3%.
研究领域:
材料科学
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纳米科技
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能源化学
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光伏器件
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表面科学
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胶体与界面化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Qiuyan Hao,Yixia Chu,Xuerong Zheng,Zhenya Liu,Liming Liang,Jiakun Qi,Xin Zhang,Gang Liu,Hui Liu,Hongjian Chen,Caichi Liu
Recently, planar perovskite solar cells based on CH 3 NH 3 PbI 3 have attracted many researcher's interest due to their unique advantages such as simple cell architecture, easy fabrication and potential multijunction construction comparing to the initial mesoporous structure. However, the preparation of planar perovskite films with high quality is still in challenge. In this paper, we developed a vapor-assisted solution process using a novel and green solvent of 1-Ethyl-2-pyrrolidone (NEP) instead of the traditional N, N-dimethylformamide (DMF) to construct a high-quality perovskite CH 3 NH 3 PbI 3 thin film with pure phase, high compactness, small surface roughness and controlled size. The phase evolution and growth mechanism of the perovskite films are also discussed. Utilizing the NEP of low volatility and moderate boiling point as solvent, we dried the PbI 2 -NEP precursor films at different temperature under vacuum and then obtained PbI 2 thin films with different crystalline degree from amorphous to highly crystalline. The perovskite films with crystal size ranged from hundreds of nanometers to several micrometers can be prepared by reacting the PbI 2 films of different crystalline degree with CH 3 NH 3 I vapor. Moreover, planar-structured solar cells combining the perovskite film with TiO 2 and spiro-OMeTAD as the electron and holes transporting layer achieves a power conversion efficiency of 10.2%.
研究领域:
材料科学
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光伏器件
·
纳米科技
·
无机非金属材料
·
能源化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2013
·Vol. 2
·期 3
·653-662
·
IF 0
Zhi Zeng,Ying Li,Jufu Deng,Qin Huang,Qiang Peng
Using tetrathienoacene (TT) and diketopyrrolopyrrole (DPP) units as donor and acceptor blocks, three new low band gap (LBG) conjugated copolymers (PTTDPO, PTTDPS and PTTDPSe) with different heterocycle bridges (furan, thiophene and selenophene) were designed and synthesized by Stille coupling polymerization reactions. Their structures were verified by 1HNMR spectroscopy and elemental analysis. All these copolymers exhibit broad absorption bands with small band gaps. UV-vis absorption spectra and cyclic voltammetry (CV) measurements indicated that the selenophene inclusion resulted in a reduction in the band gap, which could be attributed to a reduction of oxidation potentials and an increase of the electron affinities of the related copolymer. The density functional theory (DFT) calculations showed that PTTDPSe with selenophene bridges favoured a much more planar conformation than PTTDPO and PTTDPS, which afforded a higher hole mobility of 7.9 × 10−4 cm2 V−1 s−1. Photovoltaic properties of the copolymers blended with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as an electron acceptor were investigated. The polymer solar cell (PSC) based on the structure of ITO/PEDOT:PSS/PTTDPSe:PC71BM (1 : 1.5, w/w)/Ca/Al exhibited a high power conversion efficiency (PCE) of 5.68% with an improved short circuit current density (Jsc) of 15.62 mA cm−2. The primary results show that changing heterocycle bridges with different electron-donating ability can easily and finely tune the optical absorptions, band gaps and energy levels of DPP-containing copolymers. The results also demonstrate that the TT unit is a new and promising electron-donating donor block for constructing highly efficient LBG photovoltaic materials.
研究领域:
高分子化学
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材料科学
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光伏器件
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有机电子学
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能源材料
✓ 已验证
DOI
危险品化学品经营许可证（带存储）